Stretching a piercing enlarges the opening of the piercing to accommodate larger sized jewelry. It is possible to use a scalpel or dermal punch to cut ears to a large gauge hole right away, but that process is generally illegal in most states and often removes too much tissue from the earlobe, making the procedure very hard to reverse. Another popular method is to force a larger piece of jewelry into the hole, but this is generally very painful and causes a great deal of damage to the tissue. The problem with this method is that the jewelry often contains sharp edges which can damage the skin around the piercing or the jewelry size difference is too great and abrupt, which can also damage the skin around the piercing.
Another method is to push an insertion taper through the ear piercing and then transferring a piece of jewelry into the piercing by using the jewelry to push out the insertion taper. One problem with this method is that the insertion taper sizes are based on the American Wire Gauge Standard, so the size difference from one gauge to the other can be too great, which can damage the skin around the piercing during a stretch. Another issue with this method is that it requires a professional to perform the procedure. In addition during the transfer process, since there is no stable connection between the jewelry and insertion taper, often the connection is lost and the jewelry is not inserted which means another attempt to insert has to be made, which causes damage to the tissue around the piercing.